<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;">Dear Matteo<br>I follow your link and is useful for me, but when I want to study a nonmagnetic material like Tio2 ,how do I change the format of pos_file.? for NiO it is in tutorial ,but NiO is antiferromagnetic and in pos_nio.r16 you add a switch 1,-1 and 0 in front of atomic type. but for TiO2, it is nonmagnetic. How can I define the differnet type?<br>thanks a lot<br><br>Ali Kazempour<br>
Physics department, Isfahan University of Technology<br>
84156 Isfahan, Iran. Tel-1: +98 311 391 3733<br>
Fax: +98 311 391 2376 Tel-2: +98 311 391 2375<br><br>--- On <b>Thu, 7/30/09, Matteo Cococcioni <i><matteo@umn.edu></i></b> wrote:<br><blockquote style="border-left: 2px solid rgb(16, 16, 255); margin-left: 5px; padding-left: 5px;"><br>From: Matteo Cococcioni <matteo@umn.edu><br>Subject: Re: [Pw_forum] occupation<br>To: "PWSCF Forum" <pw_forum@pwscf.org><br>Date: Thursday, July 30, 2009, 11:18 AM<br><br><div class="plainMail"><br>the new tutorial on the calculation of U can be downloaded from this <br>webpage:<br><br><a href="http://www.quantum-espresso.org/wiki/index.php/QESB09#First_week" target="_blank">http://www.quantum-espresso.org/wiki/index.php/QESB09#First_week</a><br><br><br>Matteo Cococcioni wrote:<br>> Dear Ali,<br>><br>> on the wiki page of quantum-espresso you should be able to find a new <br>> tutorial on the calculation of U. Please download it<br>> and run the scripts in there following the
instructions.<br>><br>><br>><br>> ali kazempour wrote:<br>> <br>>> Dear all<br>>><br>>> From Linear response calculation ,I get for TiO2 bulk U=5.73, But when <br>>> I double the unit cell in z direction and again compute U ,I get three <br>>> different value for Ti atoms.(U=5.63,5.46,5.70).<br>>><br>>> <br>><br>> what are these three values? I assume they are what you get with <br>> supercells of three different sizes. is this correct? if it is the only <br>> strange thing is that the intermediate value is lower than the other <br>> two. otherwise you got pretty nice convergence of U which is what you <br>> want to achieve. Is there any particular reason (apart computational <br>> cost) why you only enlarge the cell in z direction?<br>><br>> <br>>> Why these values are not same . what is the main reason?
Does it in <br>>> numerical variation errors?<br>>> ANother question:<br>>> When we perturb D level by alpha, it give rise to change in d <br>>> occupancy . Is it correct that if we impose negative alpha , the <br>>> occupation becomes less than initial state .?<br>>><br>>> <br>><br>> no. positive alpha -- > decrease in total n. but you need to look at the <br>> right n....<br>><br>> <br>>> for Ti isolated atom for apha=0.1 tr[ns(na)] after first-iteration <br>>> equal to the 0.002 and at the end of calculation is 2.327 while we <br>>> know that for Ti, tr[ns(na)] =2.000. Does it seems to be correct.?<br>>><br>>> Number of iteration with fixed ns = 0<br>>> Starting ns and Hubbard U :<br>>> enter write_ns<br>>> U( 1) = 0.0000<br>>>
alpha( 1) = 0.1000<br>>> atom 1 Tr[ns(na)]= 2.0000000<br>>> atom 1 spin 1<br>>> eigenvalues: 0.4000000 0.4000000 0.4000000 0.4000000 0.4000000<br>>> eigenvectors<br>>> 1 1.0000000 0.0000000 0.0000000 0.0000000 0.0000000<br>>> 2 0.0000000 1.0000000 0.0000000 0.0000000 0.0000000<br>>> 3 0.0000000 0.0000000 1.0000000 0.0000000 0.0000000<br>>> 4 0.0000000 0.0000000 0.0000000 1.0000000 0.0000000<br>>> 5 0.0000000 0.0000000 0.0000000 0.0000000 1.0000000<br>>> occupations<br>>> 0.400 0.000 0.000 0.000 0.000<br>>> 0.000 0.400
0.000 0.000 0.000<br>>> 0.000 0.000 0.400 0.000 0.000<br>>> 0.000 0.000 0.000 0.400 0.000<br>>> 0.000 0.000 0.000 0.000 0.400<br>>> atom 1 spin 2<br>>> eigenvalues: 0.0000000 0.0000000 0.0000000 0.0000000 0.0000000<br>>> eigenvectors<br>>> 1 1.0000000 0.0000000 0.0000000 0.0000000 0.0000000<br>>> 2 0.0000000 1.0000000 0.0000000 0.0000000 0.0000000<br>>> 3 0.0000000 0.0000000 1.0000000 0.0000000 0.0000000<br>>> 4 0.0000000 0.0000000 0.0000000 1.0000000 0.0000000<br>>> 5 0.0000000 0.0000000 0.0000000 0.0000000
1.0000000<br>>> occupations<br>>> 0.000 0.000 0.000 0.000 0.000<br>>> 0.000 0.000 0.000 0.000 0.000<br>>> 0.000 0.000 0.000 0.000 0.000<br>>> 0.000 0.000 0.000 0.000 0.000<br>>> 0.000 0.000 0.000 0.000 0.000<br>>> nsum = 2.0000000<br>>> exit write_ns<br>>><br>>> <br>><br>> this is not the first iteration. this is what the initial guess of the <br>> on-site occupations the code does to start the calculation<br>><br>><br>> <br>>> Atomic wfc used for LDA+U Projector are NOT orthogonalized<br>>> Starting wfc are 9 atomic + 1 random wfc<br>>><br>>> total cpu time spent up
to now is 13.34 secs<br>>><br>>> per-process dynamical memory: 326.3 Mb<br>>><br>>> Self-consistent Calculation<br>>><br>>> iteration # 1 ecut= 45.00 Ry beta=0.70<br>>> CG style diagonalization<br>>> c_bands: 3 eigenvalues not converged<br>>> c_bands: 2 eigenvalues not converged<br>>> ethr = 1.00E-12, avg # of iterations = 40.4<br>>> enter write_ns<br>>> U( 1) = 0.0000<br>>> alpha( 1) = 0.1000<br>>> atom 1 Tr[ns(na)]= 0.0021401<br>>> atom 1 spin 1<br>>> eigenvalues: 0.0000001 0.0000001 0.0000001 0.0009883
0.0009883<br>>> eigenvectors<br>>> 1 0.0000000 -0.8803392 -0.4743427 0.0000000 0.0013927<br>>> 2 0.0000000 -0.4743432 0.8803400 0.0000000 -0.0000040<br>>> 3 0.0000000 0.0012242 0.0006642 0.0000000 0.9999990<br>>> 4 -0.8886820 0.0000000 0.0000000 -0.4585240 0.0000000<br>>> 5 0.4585240 0.0000000 0.0000000 -0.8886820 0.0000000<br>>> occupations<br>>> 0.001 0.000 0.000 0.000 0.000<br>>> 0.000 0.000 0.000 0.000 0.000<br>>> 0.000 0.000 0.000 0.000 0.000<br>>> 0.000 0.000 0.000 0.001 0.000<br>>> 0.000 0.000 0.000 0.000
0.000<br>>><br>>> <br>><br>> this is the first iteration! the problem is, in my opinion, that you <br>> didn't start this calculation from wfc and potential saved from the scf <br>> unperturbed run, but from scratch (that's why the code has to make the <br>> initial guess for the n).<br>><br>> regards,<br>><br>> Matteo<br>> <br>>> ---------------------------------- and end of the file is<br>>> :<br>>> End of self-consistent calculation<br>>> enter write_ns<br>>> U( 1) = 0.0000<br>>> alpha( 1) = 0.1000<br>>> atom 1 Tr[ns(na)]= 2.3270531<br>>> atom 1 spin 1<br>>> eigenvalues: 0.1574294 0.1574294 0.1574294 0.9273825 0.9273825<br>>> eigenvectors<br>>> 1 0.0000000 -0.4359030
-0.7986559 0.0000000 0.4148945<br>>> 2 0.0000000 0.7269732 -0.0406891 0.0000000 0.6854592<br>>> 3 0.0000000 -0.5305643 0.6004109 0.0000000 0.5983379<br>>> 4 -0.9258933 0.0000000 0.0000000 -0.3777851 0.0000000<br>>> 5 0.3777851 0.0000000 0.0000000 -0.9258933 0.0000000<br>>> occupations<br>>> 0.927 0.000 0.000 0.000 0.000<br>>> 0.000 0.157 0.000 0.000 0.000<br>>> 0.000 0.000 0.157 0.000 0.000<br>>> 0.000 0.000 0.000 0.927 0.000<br>>> 0.000 0.000 0.000 0.000 0.157<br>>><br>>><br>>> Ali Kazempour<br>>> Physics department, Isfahan University of
Technology<br>>> 84156 Isfahan, Iran. Tel-1: +98 311 391 3733<br>>> Fax: +98 311 391 2376 Tel-2: +98 311 391 2375<br>>><br>>><br>>> ------------------------------------------------------------------------<br>>><br>>> _______________________________________________<br>>> Pw_forum mailing list<br>>> <a ymailto="mailto:Pw_forum@pwscf.org" href="/mc/compose?to=Pw_forum@pwscf.org">Pw_forum@pwscf.org</a><br>>> <a href="http://www.democritos.it/mailman/listinfo/pw_forum" target="_blank">http://www.democritos.it/mailman/listinfo/pw_forum</a><br>>> <br>>> <br>><br>><br>> <br><br><br>-- <br>%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%<br>Matteo Cococcioni<br>Department of Chemical Engineering and Materials Science,<br>University of Minnesota<br>421 Washington Av. SE<br>Minneapolis, MN 55455<br>Tel. +1 612 624
9056 Fax +1 612 626 7246<br>%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% <br><br>_______________________________________________<br>Pw_forum mailing list<br><a ymailto="mailto:Pw_forum@pwscf.org" href="/mc/compose?to=Pw_forum@pwscf.org">Pw_forum@pwscf.org</a><br><a href="http://www.democritos.it/mailman/listinfo/pw_forum" target="_blank">http://www.democritos.it/mailman/listinfo/pw_forum</a><br></div></blockquote></td></tr></table><br>